1. What is Pump Shut Off Pressure?

Pump shut off pressure is the maximum pressure a pump develops when operating against a closed discharge valve (zero flow condition). It represents the highest pressure capability of the pump in a given system configuration.

2. How Does the Calculator Work?

The calculator uses the pump shut off pressure formula:

Where:

• \( P \) — Shut off pressure (psi or bar)
• \( Dead Head \) — Maximum pressure pump develops with zero flow (psi or bar)
• \( System Resistance \) — Pressure loss due to system components (psi or bar)

Explanation: The shut off pressure is the sum of the pump's dead head pressure and the system's inherent resistance when flow is completely blocked.

3. Importance of Shut Off Pressure Calculation

Details: Calculating shut off pressure is crucial for system safety, pump selection, and ensuring that all system components can withstand the maximum pressure the pump can generate.

4. Using the Calculator

Tips: Enter dead head pressure and system resistance in consistent units (psi or bar). Both values must be non-negative numbers representing pressure measurements.

5. Frequently Asked Questions (FAQ)

Q1: What is dead head pressure?
A: Dead head pressure is the maximum pressure a pump can develop when operating against a completely closed discharge, with no fluid flowing through the system.

Q2: Why is system resistance important?
A: System resistance accounts for pressure losses from valves, fittings, and piping that contribute to the overall pressure the pump must overcome even at zero flow conditions.

Q3: When should shut off pressure be calculated?
A: This calculation is essential during system design, pump selection, safety analysis, and when determining maximum operating pressures for system components.

Q4: Are there safety considerations?
A: Yes, the calculated shut off pressure should never exceed the pressure rating of any system component to prevent equipment failure and ensure operational safety.

Q5: Can this calculation be used for all pump types?
A: This calculation applies primarily to centrifugal pumps. Positive displacement pumps require different considerations as they can generate extremely high pressures when dead-headed.